Table 3.

Factors^* predicting downtime between endoscopic procedures.

Increased downtime (increased delay between procedures)	Decreased downtime (decreased delay between procedures)
High viral load in the droplet secretions (contaminant concentration)	High air changes per hour (ACH)
Heavy environmental contamination	Efficient vent system (removal efficiency)
Air stagnation	Negative pressure room availability
Large room volume	Good mixing of the air within the space

^*Final factors determining the downtime is dependent on transmission dynamics, manufacturer recommendations and contaminant concentrations.